After the Dalek asylum incident, the Doctor is called upon to investigate a ship approaching Earth in the 20th century. He gathers a team-the ancient Egyptian Queen Neferetti (Or “Neffy”) Edwardian-era hunter John Riddell, and of course, Amy and Rory-and an unexpected stowaway-Rory’s father (Mark Williams-the same actor who played Ron’s father-Arthur Weasley, in the Harry Potter film series), who just wanted to come over to fix a lightbulb.
The Doctor and co. soon discover that the ship is an old Silurian “ark”, used to carry Dinosaurs (and Silurians too, but they appear to have vanished).
Turns out the ship is sought after by black market trader Solomon, but he’s been unable to successfully steal it, causing it to head towards Earth, where it’s now in danger of being targeted as a hostile object. The Doctor isn’t too pleased with this of course, although he’s got his hands full with Velociraptors, among other things.
David Bradley, who played the Groundskeeper from the Harry Potter films.
However, the Doctor manages to safely bring the ark out of harm’s way with help from Rory and his father, and Solomon’s ship is destroyed instead, with the Dinosaurs now settling on a new planet.
They next arrive in the old west, in the town of Mercy. Turns out it’s being blockaded by a cyborg ‘gunslinger’:
Who demands the release of a “Doctor” from the town. Turns out it’s not “our” Doctor though, but the town’s physician, an alien named Jex, who has been helping the people as their physician since he rescued him. However, turns out Jex has a dark past, and was an unethical scientist who created the Cyborg, who wishes to get his revenge.
This sort of sets of a twinge of darkness in the Doctor, who wants Jex to leave or else:
Although Amy brings him back from doing something stupid. Jex decides to instead sacrifice himself to atone for his past sins, destroying himself and his ship, leaving the Cyborg gunslinger without purpose. However, the Doctor proposes a solution, that the gunslinger become the town’s protector.